Abstract [en]

Adsorption potential and characteristics of the four different indigenous materials i.e. Naturally Oxidized Iron Scrap (NOIS) sand, red soil and murum, (a type of lateritic soil which is a mix of finer and coarser grained sized particle and available in some parts of eastern India; for experimental purpose the coarser particles were used) were investigated with different operating parameters like pH, contact time, temperature, adsorbent dose and initial arsenic concentration in batch mode. From the pH study, it was found that the adsorbents were efficient in adsorbing Arsenic (As) in acidic media. Adsorption kinetics of arsenic sorption on the selected adsorbents followed Lagergren pseudo second order reaction model. The thermodynamic study evaluated that the adsorption processes of all adsorbents were exothermic in nature. The experimental equilibrium data obtained were applied to several isotherm models. Results revealed that the Freundlich isotherm was the best-fit model. The maximum adsorption capacity (q m) was found to be highest for NOIS [156 %mu;g/g for As (III) and 245 %mu;g/g for As (V)]. The batch studies ensured that the NOIS can be used as a promising adsorbent for arsenic remediation in developing indigenous treatment technologies.